If you engage the turn signal, there should be no resistance on the wheel to change lanes. 2-3 years ago that was the case, you had to force the wheel to change lanes, but not anymore. If you don't signal, you do need to wrestle with the wheel and the lane change isn't smooth at all. You shouldn't need to manually disengage anything, you'll keep TACC. You'll need to double-pull down on the stalk to re-engage autosteer once your lane change is complete.